Some time on Monday, Kevin Systrom and Mike Krieger appear to have snapped.

Tensions between the Instagram founders and their parent company had been simmering for months. But tensions are the default state at any company that has been acquired, and Systrom and Krieger had navigated those waters ably for six years.

High-level corporate executive departures generally — and Facebook departures in particular — are stage-managed to minimize drama. A replacement leader is identified and named internally. A public-relations plan is developed and put into action. An anodyne blog post announces the news. At Facebook, the executive’s departure is accompanied by well wishes, posted as status updates from Mark Zuckerberg, Sheryl Sandberg, and…